Overview

Fetal surgery is a procedure done on an unborn baby, also known as a fetus, to save the life or improve the outcome of a baby who is not developing as expected during the mother's pregnancy. This type of surgery requires a team of experts at a healthcare center that has the skills and experience to do fetal surgery.

Highly skilled fetal surgeons and their teams can treat many birth defects in babies who are not born yet. Surgery typically takes place inside the parent's uterus. Experts use fetal surgery to treat these conditions:

  • Amniotic band syndrome, when thin bands of tissue get tangled up with the fetus.
  • Bladder outlet obstruction, also called lower urinary tract obstruction (LUTO).
  • Congenital cystic adenomatoid malformation (CCAM), a mass of lung tissue that is not cancer but can continue to grow.
  • Congenital diaphragmatic hernia (CDH).
  • Congenital high airway obstruction syndrome (CHAOS), when the airway of a fetus is partly or fully blocked.
  • Fetal anemia.
  • Mediastinal teratoma, when a large mass grows in the space between the two lungs, called the mediastinum.
  • Pediatric neck mass, when there is a lump or swelling in the neck.
  • Pulmonary sequestration of the lung, a mass of lung tissue in the lower airway.
  • Sacrococcygeal teratoma (SCT), a tumor that grows from the baby's tailbone before birth.
  • Spina bifida.
  • Twin anemia-polycythemia sequence (TAPS), a form of twin-twin transfusion syndrome.
  • Twin reversed arterial perfusion (TRAP) sequence.
  • Twin-twin transfusion syndrome (TTTS).

Types

Methods for treating these conditions at highly specialized healthcare centers that do fetal surgery include:

  • Fetal endoscopic tracheal occlusion (FETO) for severe CDH.
  • In the uterus open or fetoscopic repair of myelomeningocele (my-uh-lo-muh-NING-go-seel), which is the most severe form of spina bifida.
  • Open fetal surgery for SCT resection.
  • Open fetal surgery to remove CCAM of the lung.
  • Shunt placements.
  • Fetal vesicoamniotic shunt (VAS) and fetal cystoscopy for bladder obstruction.
  • Fetoscopic laser ablation for TTTS and TAPS.
  • Bipolar cord coagulation for TRAP sequence.
  • Radiofrequency ablation for fetal tumors.
  • Ex utero intrapartum treatment (EXIT), when a doctor makes a cut in the mother's uterus to deliver the baby and clear or create an airway while the baby is still connected to the mother.
  • Fetal heart intervention.
  • Intrauterine blood transfusion, which involves injecting a donor's red blood cells into a fetus.
  • A series of infusions that add amniotic fluid to the uterus when the baby's kidneys don't develop or for complex kidney diseases.

Why it's done

Before a baby is born, early fetal surgery treatment for life-altering health problems can make outcomes better in some cases. For example, if a baby has been diagnosed before birth with spina bifida, surgeons might do fetal surgery or a less-invasive procedure using a fetoscope.

Risks

Your healthcare professional should explain the potential risks of the procedure. This includes the risks to you and those to the unborn baby. These risks include rupture of the uterus after surgery, other surgery complications, early labor, failure to treat the health problem and sometimes death of the fetus.

Results

When done by fetal surgery experts in select babies, surgery before birth can have better results than surgery after delivery. This means that children with spina bifida, for example, may have fewer major disabilities and decreased risk of an impact on the brain as they go through life than they would have if they had surgery after birth.

Clinical trials

Explore Mayo Clinic studies of tests and procedures to help prevent, detect, treat or manage conditions.

Nov. 20, 2024
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